Unveiling the temperature-dependent thermoelectric properties of the undoped and Na-doped monolayer SnSe allotropes: a comparative study

Motivated by the excellent thermoelectric (TE) performance of bulk SnSe, extensive attention has been drawn to the TE properties of the monolayer SnSe. To uncover the fundamental mechanism of manipulating the TE performance of the SnSe monolayer, we perform a systematic study on the TE properties of five monolayer SnSe allotropes such asα-,β-,γ-,δ-, andε-SnSe based on the density functional theory and the non-equilibrium Green's functions. By comparing the TE properties of the Na-doped SnSe allotropes with the undoped ones, the influences of the Na doping and the temperature on the TE properties are deeply investigated. It is shown that the figure of meritZTwill increase as the temperature increases, which is the same for almost all the Na-doped and undoped cases. The Na doping can enhance or suppress theZTin different SnSe allotropes at different temperatures, implying the presence of the anomalous suppression of theZT. The Na doping inducedZTsuppression may be caused basically by the sharp decrease of the power factor and the weak decrease of the electronic thermal conductance, rather than by the decrease of the phononic thermal conductance. We hope this work will be able to enrich the understanding of the manipulation of TE properties by means of dimensions, structurization, doping, and temperature.

Electronic structures, transport properties, and optical absorption of bilayer blue phosphorene nanoribbons

Based on first-principles density functional theory and nonequilibrium Green's function, we study the electronic band structures, the electronic transport properties, and the optical absorption of bilayer blue phosphorene nanoribbons (BPNRs). Both bilayer armchair BPNRs (a-BPNRs) and zigzag BPNRs (z-BPNRs) behave as semiconductors in the narrow nanoribbon case and metals in the wide nanoribbon case, sharply different from their monolayer counterparts where the monolayer a-BPNRs (z-BPNRs) are always semiconducting (metallic). This indicates that interlayer couplings or the increasing layer number may induce the switching of the conductivity of the monolayer BPNRs, which is absent in graphene and phosphorene nanoribbons. Furthermore, we explore the edge states of the energy bands near Fermi energy, and find that there are almost no pure edge-state band branches in the bilayer BPNRs, which can be attributed to the interlayer couplings between the edge-states in one layer and the bulk-states in the other. Consequently, the resulting complex band structures cannot be directly analyzed any more in the framework of the two-body coupling picture just according to the simple band structures of the monolayer BPNRs. Finally, we present the current-voltage characteristics and the optical absorption of the bilayer a-BPNRs and z-BPNRs. The influences of the nanoribbon width and the interlayer couplings on the current and the anisotropic optical absorption can be understood based on the complex energy band structures. This research should be an important reference of extending the field of BPNRs from the monolayer to the bilayer case, and deepen the understanding of the difference between the monolayer and bilayer nanoribbons in different materials.

[Application of pretrained model based on electronic medical record in recognition of acute respiratory infection]

Objective: To evaluate the recognition of acute respiratory infection (ARI) by a pretrained model based on electronic medical records (EMRs). Methods: 38 581 EMRs were obtained from Chongqing University Three Gorges Hospital in December 2021. Bidirectional encoder representation from transformers (BERT) pretrained model was used to identify ARI in EMRs. The results of medical professionals were considered as the gold standard to calculate the sensitivity, specificity, Kappa value, and area under the curve of the receiver operating characteristic (AUC). Results: There were 3 817 EMRs in the test set, with 1 200 ARIs. A total of 1 205 cases were determined as ARI by the model, with a sensitivity of 92.67% (1 112/1 200) and a specificity of 96.45% (2 524/2 617). The model identified ARI with similar accuracy in males and females (AUCs 0.95 and 0.94, respectively), and was more accurate in identifying ARI cases in those aged less than 18 than in adults 18-59 and adults 60 and older (AUCs 0.94, 0.89 and 0.94, respectively). The current model had a better identification of ARIs in outpatient patients than that in hospitalized patients, with AUCs of 0.74 and 0.95, respectively. Conclusion: The use of the BERT pretrained model based on EMRs has a good performance in the recognition of ARI cases, especially for the outpatients and juveniles. It shows a great potential to be applied to the monitoring of ARI cases in medical institutions.

Improvement of goose embryonic and muscular developments by wider angle egg turning during incubation and the regulatory mechanisms

Egg turning during incubation plays important roles in achieving high hatching performance and gosling quality. The objective of this study was to improve embryonic and muscular developments so to achieve better gosling quality by wider egg turning angles during incubation, and to unravel the associated regulatory molecular mechanisms. In each of three consecutive incubations, 1,728 goose eggs were divided into 3 groups that were set in the same type of commercial incubators with turning angles adjusted differently to 50°, 60°, and 70°, respectively. On average of the 3 tests, incubation with wider 70° turning angle reduced the post-18-day embryo mortality, promoted embryonic growth and development, improved the hatchability and gosling quality. On embryonic day of 29, gene mRNA expression levels of the hypothalamic growth hormone-releasing hormone (GHRH), pituitary growth hormone (GH), and liver insulin-like growth factor 1 (IGF-1) were higher in the 70° turning group than in the 50° or 60° groups. Wider angle turning also increased mRNA expression levels of the muscle development regulatory genes such as MYF5, MyoD, Myogenin (MyoG), and MRF4. Changes in expression of the above genes, together with the upregulation of the Pax3 and Pax7 genes in leg muscles, well explained the enhancement of the muscular growth and development when eggs were incubated by wider turning angles. These results also extended our understanding of the impacts and mechanisms of egg turning during incubation on hatching performance and gosling quality.

[Clinical characteristics of patients with antisynthetase syndrome and interstitial pulmonary disease]

Objective: To provide reference for clinicians in diagnosis and treatment of antisynthetase syndrome with interstitial pulmonary disease (ASS-ILD) by analyzing the clinical features, imaging features and pulmonary function changes of ASS-ILD patients. Methods: A total of 92 patients with ASS-ILD diagnosed in the Respiratory Center of China-Japan Friendship Hospital from January 2015 to May 2018 were included, clinical manifestations, high-resolution computed tomography (HRCT), pulmonary function test, treatment and outcome were retrospectively analyzed. Results: The average age of the 92 patients was (58.6±12.2) years with a ratio of male to female 1∶1.79. The main types of anti-synthetase antibody were anti-Jo-1 antibody (37 cases, 40.2%) and anti EJ antibody (26 cases, 28.3%). The most common symptoms of ASS-ILD were cough (79 cases, 85.9%), shortness of breath (60 cases, 65.2%), expectoration (54 cases, 58.7%), fever (34 cases, 36.9%), and common signs were craftsman's hand (30 cases, 32.6%) and joint pain (23 cases, 25.0%). The most common imaging findings in HRCT were ground-glass opacities(68 cases, 73.9%), reticulations (45 cases, 48.9%), tractive bronchiectasis (40 cases, 43.5%) and consolidation (39 cases, 42.4%). The most common types of ILD were non-specific interstitial pneumonia (NSIP) (63 cases, 68.5%), followed by NSIP-organic pneumonia (OP) (12 cases, 13.0%). The main type of lung function impairment was mild restrictive ventilation dysfunction. There were no significant differences in clinical features, imaging findings and pulmonary function changes in different subtypes of ASS-ILD patients (all P>0.05). Corticosteroids was used in 78 (84.8%) of ASS-ILD patients, and 34 cases (37.0%) were given cyclophosphamide. A total of 91 patients (98.9%) were discharged with improvement and 1 anti-EJ positive patient died. Conclusions: ASS-ILD occurs frequently in middle-aged and old women. Respiratory symptoms, craftsman's hands and arthritis are the most common clinical manifestations. The most common imaging types of ILD are NSIP and NSIP-OP. Corticosteroids is commonly used for treatment.

[When COVID-19 encounters interstitial lung disease: challenges and management]

In December 2019, a new type of coronavirus pneumonia (COVID-19) emerged in Wuhan, Hubei, and spread rapidly to China. The lung injury and repair caused by COVID-19 has many similarities with the onset and progression of interstitial lung disease (ILD) . Therefore, it is difficult to distinguish between COVID-19 and some types of new-onset ILD or other causes leading to acute exacerbation of ILD. Clinicians need to comprehensively analyze the epidemic history, disease onset characteristics, clinical manifestations, image characteristics, serological andpathogenic microorganism test results to confirm diagnosis. Because of this, the article will discuss the issues related to the differential diagnosis and management of COVID-19 and ILD, and try to provide reasonable suggestions.

[Differences in small airway lesions in patients with different types of idiopathic interstitial pneumonia]

Objective: To investigate the differences in small airway lesions in patients with different types of idiopathic interstitial pneumonia (IIPs). Methods: A total of 46 patients with IIPs confirmed by video assisted thoracoscopic or open lung biopsy, hospitalized in the Respiratory and Critical Care Medicine of Beijing Chao-Yang Hospital, from Dec. 1998 through Nov. 2007 were studied, including 19 patients with idiopathic pulmonary fibrosis (IPF group), 14 with nonspecific interstitial pneumonia (NSIP group), and 13 cryptogenic organizing pneumonia (COP group). Pulmonary function and high resolution CT (HRCT) of the patients were examined before lung biopsy, and lung biopsy tissue were stained with hematoxylin-eosin. The abnormality of small airways in pathology, pulmonary function and HRCT were compared among these patients with IIPs. Results: Small airway inflammatory cell infiltration score (53.8±17.7) was significantly higher in the COP group than in the IPF group (38.8±9.7) (P<0.01). The fibrous tissue proliferation score in small airways (42.9±12.1) in the IPF group was significantly higher than that in the NSIP group (31.4±10.5) and the COP group (26.7±16.3) (both P<0.05). In the IPF group, NSIP group and COP group, the small airway function index was significantly reduced, and the maximum expiratory flow rate (V(25%), V(50%)) at 25% and 50% of the lung capacity was<80% predicted, the incidences of small airway dysfunction in the three groups were 63.2%, 69.2%, and 63.6%, respectively. There was no significant difference among the groups (P>0.05). Small airway inflammatory cell infiltration was negatively correlated with V(50%) of small airway function (r=-0.305, P=0.049). The bronchodilation rate in the HRCT of the IPF group (100%) was significantly higher than that of the NSIP group (50.0%) and the COP group (53.8%) (both P<0.01). Conclusion: The patients with IPF, NSIP and COP have abnormal pathologic, physiological and imaging changes of small airways, moreover have different characteristics.

[Clinical features of acute diffuse pulmonary exudative disorders]

Objective: To analyze the clinical features of acute diffuse pulmonary exudative disorders. Methods: The data were collected from patients who were hospitalized in respiratory intensive care unit (RICU) of Beijing Chaoyang Hospital affiliated to the Capital Medical University during January 2009 to December 2011, and had acute clinical course with imaging findings of diffuse pulmonary infiltrated shadows (similar to acute respiratory distress syndrome (ARDS)). The causes of disease and clinical features were analyzed. Results: A total of 86 patients with acute diffuse pulmonary exudative disorders were included. Sixty-two (72.1%) were males, with a mean age of (58.6±16.4) years old; 24(27.9%) were females, with a mean age of (48.2±18.3) years old. The duration of the disease before administration was (11.5±5.2) days, and RICU stay was (15.5±9.5) days, with hospital mortality of 40.7% and the average hospitalization cost of 101 thousand RMB. The main cause was infection, which occurred in 53 cases (61.6%) (virus in 21 cases, bacteria in 14 cases, fungus in 11 cases, pneumocystis in 15 cases and others in 3 cases, mixed infection in 11 cases). Interstitial pneumonia occurred in 12 cases (idiopathic interstitial pneumonia in 9 cases: cryptogenic organizing pneumonia in 3 cases, the acute exacerbation of idiopathic pulmonary fibrosis in 3 cases, nonspecific interstitial pneumonia in 1 case, acute interstitial pneumonia in 2 cases, and connective tissue disease in 3 cases), aspiration pneumonia in 10 cases, acute left heart failure in 6 cases, and exogenous pulmonary ARDS in 5 cases. Conclusions: The main cause of acute diffuse pulmonary exudative disorders is pulmonary infection, followed by interstitial pneumonia. The hospital mortality and hospitalization cost are high.

Coherent spin precession via photoinduced antiferromagnetic interactions in La0.67Ca0.33MnO3

Pronounced spin precessions are observed in a geometry with negligible canting of the magnetization in ferromagnetic La(0.67)Ca(0.33)MnO(3) thin films using the time-resolved magneto-optical Kerr effect. The precession amplitude monotonically decreases with increasing field, indicating that the coherent spin rotation may be triggered by a transient exchange field and not by demagnetization and/or anisotropy field modulation. We attribute the transient exchange field to emergent antiferromagnetic interactions due to charge transfer and modification of the kinetic energy of e(g) electrons under optical excitation.

Observation of insulating nanoislands in ferromagnetic GaMnAs

Resonant Raman data on ferromagnetic GaMnAs reveal the existence of a new kind of defect: insulating nanoislands consisting of substitutional MnGa acceptors surrounded by interstitial MnI donors. As indicated by the observation of a sharp 1S3/2-->2S3/2 Raman transition at approximately 703 cm(-1), the acceptor-bound holes inside the islands are isolated from the metallic surroundings. Instead, Mn-bound excitons do couple to the ferromagnetic environment, as shown by the presence of associated Raman magnon side bands. This leads to an estimate of 5-10 nm for the nanoisland radius. The islands disappear after annealing due to the removal of the MnI ions.

Ultrafast photoinduced reflectivity transients in doped manganite

The temperature and magnetic field dependence of ultrafast photoinduced spin and quasiparticle relaxation dynamics is reported in La(0.67)Ca(0.33)MnO(3) and LaMnO(3) single crystals and thin films. Both manganites reveal an unusually slow ( approximately 10 micros) carrier relaxation process attributed to the spin-lattice relaxation in localized states. The quasiparticle dynamics is governed by the temperature- and magnetic field-dependent pseudogap in La(0.67)Ca(0.33)MnO(3), and by the temperature-independent Jahn-Teller gap in LaMnO(3). The loss of spectral weight near the Fermi level in La(0.67)Ca(0.33)MnO(3) strongy affects the quasiparticle relaxation dynamics as temperature increases from below T(C). Our results show that the coupled dynamics of charge, spin and lattice is strongly correlated with the distinct gap structures in these manganites.

GABA(B) receptor agonist baclofen attenuates the development and expression of d-methamphetamine-induced place preference in rats

The present study investigated the effect of systemic administration of the GABA(B) receptor agonist, baclofen, on the development and expression of d-methamphetamine (d-MA)-induced place preference in male Wistar rats. Using a biased and 8-day schedule of conditioning, it was found that administration of d-MA (0.5 mg/kg, i.p.) produced significant place preference. The administration of baclofen (2.5 and 5.0 mg/kg, i.p.) 30 min prior to the exposure to d-MA attenuated the development of d-MA-induced place preference (p<0.05). In addition, when it was acutely administered 30 min prior to the testing session of an already established d-MA place preference, baclofen (1.25-5.0 mg/kg, i.p.) attenuated the expression of this conditioned response in a dose-dependent manner. These results showed that baclofen suppressed the rewarding effect produced by d-MA and may be potentially effective in the treatment of methamphetamine dependence and craving.

Influence of tramadol on morphine discriminative behavior in rats

AIM

To study the potential of the psychological dependence of tramadol.

METHODS

Rats were trained to discriminate 4.0 mg/kg morphine, and to discriminate 0.5 mg/kg methamphetamine (MA) from saline under a fixed-ratio (FR10) schedule of reinforcement. After they acquired the discrimination, different doses of tramadol were used to substitute for training dose of morphine and MA. Naltrexone was injected concomitantly with tramadol.

RESULTS

Tramadol fully substituted morphine at a dose of 32 mg/kg or higher. The ED50 value of the discriminative effects of tramadol was 20.94 mg/kg, higher than that of morphine (2.04 mg/kg, P < 0.01). MA failed to generalize to tramadol at the doses tested. Naltrexone antagonized the discriminative response of tramadol.

CONCLUSION

Tramadol can substitute for morphine in morphine discriminative rats. The discriminative stimulus effects of tramadol are mediated by a mu opioid mechanism.